rdf/util/nsRDFResource.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsRDFResource.h"
   7 #include "nsIServiceManager.h"
   8 #include "nsIRDFDelegateFactory.h"
   9 #include "nsIRDFService.h"
  10 #include "nsRDFCID.h"
  11 #include "prlog.h"
  12 #include "nsComponentManagerUtils.h"
  13 #include "nsServiceManagerUtils.h"
  14
  15 static NS_DEFINE_CID(kRDFServiceCID, NS_RDFSERVICE_CID);
  16
  17 nsIRDFService* nsRDFResource::gRDFService = nullptr;
  18 nsrefcnt nsRDFResource::gRDFServiceRefCnt = 0;
  19
  20 ////////////////////////////////////////////////////////////////////////////////
  21
  22 nsRDFResource::nsRDFResource(void)
  23     : mDelegates(nullptr)
  24 {
  25 }
  26
  27 nsRDFResource::~nsRDFResource(void)
  28 {
  29     // Release all of the delegate objects
  30     while (mDelegates) {
  31         DelegateEntry* doomed = mDelegates;
  32         mDelegates = mDelegates->mNext;
  33         delete doomed;
  34     }
  35
  36     if (!gRDFService)
  37         return;
  38
  39     gRDFService->UnregisterResource(this);
  40
  41     if (--gRDFServiceRefCnt == 0)
  42         NS_RELEASE(gRDFService);
  43 }
  44
  45 NS_IMPL_ISUPPORTS(nsRDFResource, nsIRDFResource, nsIRDFNode)
  46
  47 ////////////////////////////////////////////////////////////////////////////////
  48 // nsIRDFNode methods:
  49
  50 NS_IMETHODIMP
  51 nsRDFResource::EqualsNode(nsIRDFNode* aNode, bool* aResult)
  52 {
  53     NS_PRECONDITION(aNode != nullptr, "null ptr");
  54     if (! aNode)
  55         return NS_ERROR_NULL_POINTER;
  56
  57     nsresult rv;
  58     nsIRDFResource* resource;
  59     rv = aNode->QueryInterface(NS_GET_IID(nsIRDFResource), (void**)&resource);
  60     if (NS_SUCCEEDED(rv)) {
  61         *aResult = (static_cast<nsIRDFResource*>(this) == resource);
  62         NS_RELEASE(resource);
  63         return NS_OK;
  64     }
  65     else if (rv == NS_NOINTERFACE) {
  66         *aResult = false;
  67         return NS_OK;
  68     }
  69     else {
  70         return rv;
  71     }
  72 }
  73
  74 ////////////////////////////////////////////////////////////////////////////////
  75 // nsIRDFResource methods:
  76
  77 NS_IMETHODIMP
  78 nsRDFResource::Init(const char* aURI)
  79 {
  80     NS_PRECONDITION(aURI != nullptr, "null ptr");
  81     if (! aURI)
  82         return NS_ERROR_NULL_POINTER;
  83
  84     mURI = aURI;
  85
  86     if (gRDFServiceRefCnt++ == 0) {
  87         nsresult rv = CallGetService(kRDFServiceCID, &gRDFService);
  88         if (NS_FAILED(rv)) return rv;
  89     }
  90
  91     // don't replace an existing resource with the same URI automatically
  92     return gRDFService->RegisterResource(this, true);
  93 }
  94
  95 NS_IMETHODIMP
  96 nsRDFResource::GetValue(char* *aURI)
  97 {
  98     NS_ASSERTION(aURI, "Null out param.");
  99
 100     *aURI = ToNewCString(mURI);
 101
 102     if (!*aURI)
 103         return NS_ERROR_OUT_OF_MEMORY;
 104
 105     return NS_OK;
 106 }
 107
 108 NS_IMETHODIMP
 109 nsRDFResource::GetValueUTF8(nsACString& aResult)
 110 {
 111     aResult = mURI;
 112     return NS_OK;
 113 }
 114
 115 NS_IMETHODIMP
 116 nsRDFResource::GetValueConst(const char** aURI)
 117 {
 118     *aURI = mURI.get();
 119     return NS_OK;
 120 }
 121
 122 NS_IMETHODIMP
 123 nsRDFResource::EqualsString(const char* aURI, bool* aResult)
 124 {
 125     NS_PRECONDITION(aURI != nullptr, "null ptr");
 126     if (! aURI)
 127         return NS_ERROR_NULL_POINTER;
 128
 129     NS_PRECONDITION(aResult, "null ptr");
 130
 131     *aResult = mURI.Equals(aURI);
 132     return NS_OK;
 133 }
 134
 135 NS_IMETHODIMP
 136 nsRDFResource::GetDelegate(const char* aKey, REFNSIID aIID, void** aResult)
 137 {
 138     NS_PRECONDITION(aKey != nullptr, "null ptr");
 139     if (! aKey)
 140         return NS_ERROR_NULL_POINTER;
 141
 142     nsresult rv;
 143     *aResult = nullptr;
 144
 145     DelegateEntry* entry = mDelegates;
 146     while (entry) {
 147         if (entry->mKey.Equals(aKey)) {
 148             rv = entry->mDelegate->QueryInterface(aIID, aResult);
 149             return rv;
 150         }
 151
 152         entry = entry->mNext;
 153     }
 154
 155     // Construct a ContractID of the form "@mozilla.org/rdf/delegate/[key]/[scheme];1
 156     nsAutoCString contractID(NS_RDF_DELEGATEFACTORY_CONTRACTID_PREFIX);
 157     contractID.Append(aKey);
 158     contractID.AppendLiteral("&scheme=");
 159
 160     int32_t i = mURI.FindChar(':');
 161     contractID += StringHead(mURI, i);
 162
 163     nsCOMPtr<nsIRDFDelegateFactory> delegateFactory =
 164              do_CreateInstance(contractID.get(), &rv);
 165     if (NS_FAILED(rv)) return rv;
 166
 167     rv = delegateFactory->CreateDelegate(this, aKey, aIID, aResult);
 168     if (NS_FAILED(rv)) return rv;
 169
 170     // Okay, we've successfully created a delegate. Let's remember it.
 171     entry = new DelegateEntry;
 172     if (! entry) {
 173         NS_RELEASE(*reinterpret_cast<nsISupports**>(aResult));
 174         return NS_ERROR_OUT_OF_MEMORY;
 175     }
 176
 177     entry->mKey      = aKey;
 178     entry->mDelegate = do_QueryInterface(*reinterpret_cast<nsISupports**>(aResult), &rv);
 179     if (NS_FAILED(rv)) {
 180         NS_ERROR("nsRDFResource::GetDelegate(): can't QI to nsISupports!");
 181
 182         delete entry;
 183         NS_RELEASE(*reinterpret_cast<nsISupports**>(aResult));
 184         return NS_ERROR_FAILURE;
 185     }
 186
 187     entry->mNext     = mDelegates;
 188
 189     mDelegates = entry;
 190
 191     return NS_OK;
 192 }
 193
 194 NS_IMETHODIMP
 195 nsRDFResource::ReleaseDelegate(const char* aKey)
 196 {
 197     NS_PRECONDITION(aKey != nullptr, "null ptr");
 198     if (! aKey)
 199         return NS_ERROR_NULL_POINTER;
 200
 201     DelegateEntry* entry = mDelegates;
 202     DelegateEntry** link = &mDelegates;
 203
 204     while (entry) {
 205         if (entry->mKey.Equals(aKey)) {
 206             *link = entry->mNext;
 207             delete entry;
 208             return NS_OK;
 209         }
 210
 211         link = &(entry->mNext);
 212         entry = entry->mNext;
 213     }
 214
 215     NS_WARNING("nsRDFResource::ReleaseDelegate() no delegate found");
 216     return NS_OK;
 217 }
 218
 219
 220
 221 ////////////////////////////////////////////////////////////////////////////////